(1) Field of the Invention
The present invention relates to a view restriction method, a view restriction setting method, a receiver and a device and a program for setting view restriction. More particularly, the present invention relates to a scheme of restricting view of programs on the basis of the contents thereof.
(2) Description of the Related Art
Recently, the necessity of view restriction based on the contents of TV programs has been pointed out because violent and obscene programs are prejudicial to children. A technique has been developed in which television sets are equipped with a particular device capable of automatically blocking specific video programs that may be prejudicial to children, such as violent scene and excessive sex depiction. Such view restriction is implemented by, for example, a so-called V-chip (Violence chip).
The V-chip has a blocking mechanism in which the broadcasting station rates each program based on the degree of violence or obscene, and translates the rating value thus obtained into a corresponding signal, which is then broadcasted in the form of radio wave. If the television set equipped with the V-chip of blocking violent scene detects a rating value equal to or greater than the threshold value, it automatically prevents the corresponding video from view.
This makes it possible to protect the TV viewer of under the specified age from a detrimental program. Presently, the use of V-chip has been mandated in digital broadcasting in the United States and Canada. The V-chip technique allows the setting of blocking violent programs to be released to view such programs by inputting the password into the TV set.
A program-selecting function called VPS (Video Program System) is known as a technique similar to the V-chip. According to VPS, the broadcasting station restricts the allowable program contents on the broadcast time range. When a program content adverse to the time range based restriction is broadcasted, the broadcasting station superposes a signal indicating out-of-restriction on the broadcasting wave of the program.
The receiver compatible with the VPS receives the signal indicating whether the associated program is adverse to the time range based restriction, and recognizes that the broadcasted program easily ruins children's corporal, mental and emotional healthy. Then, the receiver blocks the program from view. However, if the password consisting of four digits is applied to the receiver, the blocking is disabled. At present, the VPS is mandated in some states in Germany.
The use of V-chip or VPS has not yet been mandated in the digital broadcasting in Japan for several reasons. However, the rating value may be assigned to each program. If the TV viewer sets a parental password (parental lock) in his/her receiver, a specified rated program will be placed out of view.
It is to be noted that the rating in the conventional view restriction method using the V-chip or VPS is based on the uniform standard. This does not allow the parents to block a program that does not contain violent scene or obscene scene but is prejudicial to children from an educational or moral viewpoint.
In addition, the V-chip or VPS allows the blocking to be easily released due to leakage of the parental password. This makes it difficult to surely protect children from unwanted programs.